Do not believe in anything simply because you have heard it.
“Do not believe in anything simply because you have heard it. Do not believe in anything simply because it is spoken and rumored by many. Do not believe in anything simply because it is found written in your religious books. Do not believe in anything merely on the authority of your teachers and elders. Do not believe in traditions because they have been handed down for many generations. But after observation and analysis, when you find that anything agrees with reason and is conducive to the good and benefit of one and all, then accept it and live up to it.”
People with opinions just go around bothering each other.
~ The Buddha (Sutta Nipata, Magandiya Sutta)
Actions are to be done with repeated reflection
“Whenever you want to do a bodily action, you should reflect on it: ‘This bodily action I want to do—would it lead to self-affliction, to the affliction of others, or to both? Would it be an unskillful bodily action, with painful consequences, painful results?’ If, on reflection, you know that it would lead to self-affliction, to the affliction of others, or to both; it would be an unskillful bodily action with painful consequences, painful results, then any bodily action of that sort is absolutely unfit for you to do. But if on reflection you know that it would not cause affliction… it would be a skillful bodily action with pleasant consequences, pleasant results, then any bodily action of that sort is fit for you to do.”
The Buddha said, “Subhuti, if, then, a man or
woman filled as many worlds as that with the seven
jewels and gave them as a gift to the tathagatas, the
arhans, the fully-enlightened ones, and a noble son
or daughter grasped but one four-line gatha of this
dharma teaching and made it known and explained
it to others, the body of merit produced as a result
would be immeasurably, infinitely greater.”